<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>10.流程控制-分支结构-if语句-练习1</title>
    <script>
        //练习1
        var age = prompt('请输入您的年龄');
        if (age >= 18) {
            alert('您已年满18岁，可以访问');
        } else {
            alert('您未满18岁，禁止访问');
        }
    </script>
</head>

<body>

</body>

</html>